Control of terrestrial mollusks

ABSTRACT

METHOD OF CONTROLLING TERRESTRIAL MOLLUSKS USING HEXAMETHYLDITIN AS ACTIVE AGENT.

United States Patent O 3,557,289 CONTROL OF TERRESTRIAL MOLLUSKS Obren Keckemet, Tacoma, Wash., assignor to Penuwalt Corporation, Philadelphia, Pa., a corporation of Pennsylvania No Drawing. Filed Mar. 7, 1969, Ser. No. 805,377 Int. Cl. A01n 9/00 US. Cl. 424288 Claims ABSTRACT OF THE DISCLOSURE Method of controlling terrestrial mollusks using hexamethylditin as active agent.

Terrestrial mollusks such as slugs, snails, and the like are well known enemies of plant cultivation. Mollusks destroy practically all substances of vegetable origin and are both a nuisance and economic hazard to growers of various products, including field crops, citrus fruit growers and particularly, vegetable growers, nurseries and home gardeners. Because mollusks multiply so rapidly they can quickly destroy all the seedlings or devour all the harvest in a cultivated area. It is a known fact that a mollusk can eat its own weight in two days.

In accordance with this invention, there is provided a method for controlling terrestrial mollusks comprising the application to an area to be controlled, a molluskicidal amount of hexamethylditin.

The active agent used in the invention, hexamethylditin, is a known compound and may be prepared in accordance with the procedures set forth by G. Gruttner, Chem. Ber. 50, 1808 (1917), or by other known methods. In preparing the composition of the invention for combating mollusks, a carrier will be mixed with molluskicidal amount of hexamethylditin, which amount for spot treatments will be preferably in the range of about from 0.01% to about by weight of the total composition. On a pound per acre basis, from about 0.1 to about 10 pounds per acre of active ingredient will be used. IIt will be understood that the carrier plus active agent may also embody other materials such as baits for attracting mollusks and other agents may be present such as those which help in the application or distribution of the agent. The carrier may, of course, be a liquid or solid carrier and the compositions may be made in the form of a paste which may be spread on the soil whereby the mollusks come in contact with the composition. In liquid formulations the hexamethylditin will preferably be dispersed with or without suspending agents in liquid solvents. Where a solid carrier is used, a carrier may be any one of the well known readily available finely divided solids such as vermiculites, cellulosic materials, sand, silicates, and the like.

As indicated, the invention is applicable to the control of terrestrial mollusks and it is surprising that hexamethylditin is specific to this type of organism. Particular mollusks which have been tested and which are responsive to the hexamethylditin include, but are not limited to, Arion 3,557,289 Patented Jan. 19, 1971 ice ater (European black slug), Helix aspersa (brown garden snail.) Limax maximius (spotted garden slug), and Deroceras reticulatum (grey garden slug). In order to further illustrate the invention the following examples are given.

EXAMPLE 1 Formulations (A) Typical bait formulation: Percent Hexamethylditin 1 0.25 Bait-carrier 2 98.75 Sticker 3 1.00

1 Dissolved in acetone to facilitate incorporation.

A lfalfa flour, mill run wheat bran, yeast or ground apple pumice.

3 Polyvinyl alcohol.

(B) Typical solvent formulation:

These formulations can be sprayed, dusted or otherwise applied or can be made into a paste or any other suitable form.

EXAMPLE 2 Evaluations were made at approximately 62 F. Each of three replications consisted of five animals in a testing box constructed with an open arena of moist soil and covered refuge containing wet peat moss. The test baits were formulated on mill-run wheat bran with acetone added to dissolve and incorporate the chemicals. A small pile of bait in the center of the arena was the only source of food for the animals in each test box. Observations were made at regular intervals of numbers of animals lying (usually affected by the chamicals) in the arenas, or dead. Death was determined by tapping immobile animals with a pencil, animals being recorded as dead if no sign of contraction was seen.

The following Table 1 indicates the data obtained.

TABLE L-EFFECT OF HEXAMETHYLDITIN FOR CONTROL OF MOLLUSKS Number of slugs after Concentra- Percent tion of 48 hours 7 days after agents, 4 days, 14 days, 14 days Mollusk percent Affected Dead dead Afiected Dead dea dead Arz'on ater 1. 0 3 0 5 0 l2 12 80. 0 0. 5 3 0 3 0 13 15 100. 0 0. 25 2 0 1 2 11 13 86. 7

Helix aspersa 1. 0 8 1 3 2 9 15 100. 0 0. 5 ll 0 6 0 12 15 100. 0 0. 25 7 0 3 1 10 15 100. 0 1. 0 11 0 7 1 12 15 100. 0 0. 5 8 0 5 0 11 15 100. 0 0. 25 5 1 4 1 8 13 83. 3

Limax mazz'mus 0.25 3 1 5 5 5 100. 0

3 4 EXAMPLE 3 It is obvious from the above table that only hexa- Following the test procedure of Example 2, numerous methylditin and hexapropylditin have no effect on aquatic homologues of hexamethylditin were evaluated and slugs but as can be Seen from Tables H and HI heXa 9533 3 2; lrfilauvely meficectlve' The data follows In 5 propylditin is without significant effect against terrestrial TABLE II {Effect of various agents on Helix aspcrsa (brown garden snail)] Concentra- Percent tion of 48 Hours 7 Days dead agent, 4 days, after Agent tested percent Affected Dead Dead Afieeted Dead 14 days l-Iexamethylditin 1 7 1 5 15 100. 0 Hexaethylditin- 1 3 0 2 1 2 33. 3 Hexapropylditin" 1 4 0 0 1 0 0. 0 Hexaisobutylditin- 1 7 0 1 3 2 26. 7 Hexabntylditin- 1 5 0 0 2 0 0. 0 Hexaamylditin 1 10 1 1 2 3 33. 3 Untreated Check 2 0 0 4 0 13. 3

TABLE III [Efieet of various agents on Derocems reticulatum (grey garden slug)] Goncentra- Percent tion of 48 hours 7 days dead agent, after Agent tested percent Atfeeted Dead Afiected Dead 7 days Hexamethylditin 1 8 4 l 14 93. 3

Untreated check 1 0 2 O 0. 0

EXAMPLE 4 slugs. Thus, the tables of data clearly illustrate the un- A i il (Pl b corneas) were exposed to expected specific effect of hexamethylditin as a terrestrial various hexaalkylditin by adding the formulated agent to 11 i0id8.

water containing the organisms. The following Table IV 40 I claim: indicates the results obtained: 1. A method for controlling terrestrial mollusks which TABLE IV Formulation and concentration, p.p.m. Effects after- 10% in cellosolve Agent tested tested at- 6 hours 24 hours 48 hours Hexamethylditin isopropanol tested at- Hexabutylditln Hexaisobutyldltin 10% in isopropanol tested at- Hexa r0 lditln 1 None None p py 2.5 do d 5% in isopropanol tested at- Hexaamyldltin 1 d0 Bleeding. 2 dead:

5 do Dead.

Contr l comprises contacting said mollusks with a molluskicidal References Cited r amount Of hexamethylditin. UNITED STATES PATENTS M821 The method of 01am 1 where the mollusk 1s Arzolz 4 1 6 1 23 g g T 424 288 j -,3} math Clam 1 Where the musk 18 3:45:33; 311369 irbiii ijiiiiiiii152L333 4. The method of claim 1 where the mollusk is Limax OTHER REFERENCES Chemical Abstracts 67: 1076382 (1967).

5. The method of claim 1 where the mollusk is Dero- Cems reticulaflm 1n JEROME D. GOLDBERG, Primary Examiner @35 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Inventor-(s) Obren Keckemet, Tacoma, Washington. I

It is certified that error appeers In the eboTxe-identiffid ratent and that said Letters Patent are hereby corrected as shown below:

In Cdlufhfi 21 line 26 "'Tkamthyld ifi fi' hbfiId red IIexamefhy] InColumh 2; '11ne'3'4 "Texamet'hglditin Should read -'-"Hxanithy1 Signed and sealed this 11th day oi May 1971 (SEAL) Attest:

EDWARD M.FLETGHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents V v I v 

